Abstract
The aim of this study was to examine the internal consistency reliability, test–retest reliability, factorial structure validity, and convergent validity of a Korean version of the Satisfaction With Life Scale adapted for children (K-SWLS-C). Participants consisted of 653 elementary school students (48% were male). The internal consistency of the K-SWLS-C was .93, and its test–retest reliability was .62 for inter-test period of 4 weeks. Confirmatory factor analysis showed that the K-SWLS-C had the unifactorial structure reported in previous studies. The K-SWLS-C was found to be significantly associated with domains of student life satisfaction. The findings of the present study suggest that the K-SWLS-C is a well-developed instrument for measuring life satisfaction among Korean children.
Life satisfaction refers to a “judgmental process, in which individuals assess the quality of their lives on the basis of their own unique criteria” (Pavot & Diener, 1993, p. 164). Life satisfaction is a cognitive component of subjective well-being, which refers to a combination of positive emotions, negative emotions, and cognitive judgment of life (Diener, Emmons, Larsen, & Griffin, 1985), and is not only an outcome of positive life events but also a predictor of favorable life outcomes (Lyubomirsky, King, & Diener, 2005).
The Satisfaction With Life Scale (SWLS; Diener et al., 1985) is one of the most widely used instruments for assessing life satisfaction, and has been translated into and validated in several languages including French (Blais, Vallerand, Pelletier, & Briere, 1989), Dutch (Arrindell, Heesink, & Feij, 1999), Spanish (Atienza, Pons, Balaguer, & García-Merita, 2000), Russian (Tucker, Ozer, Lyubomirsky, & Boehm, 2006), Taiwanese (Wu & Yao, 2006), and Turkish (Durak, Senol-Durak, & Gencoz, 2010) to enable researchers to conduct cross-cultural research on life satisfaction.
However, there is a growing need for developmental studies on life satisfaction across ages, and for this reason, the Satisfaction With Life Scale adapted for children (SWLS-C) was developed (Gadermann, Schonert-Reichl, & Zumbo, 2010). The SWLS-C was devised using the adult version as a basis, but its items are phrased in a manner understood by children. In addition, items of the SWLS-C are scored using a 5-point Likert-type scale, whereas items of the SWLS are scored using a 7-point Likert-type scale (Gadermann et al., 2010).
There are several reasons why the SWLS-C should be validated in Korea and for use with Korean children. First, the Korean version of the SWLS (K-SWLS) has been used to conduct numerous studies, and others are in progress. The K-SWLS was chosen for these studies because when Korean researchers are interested in the developmental aspects of life satisfaction, they need a scale for children that corresponds to the adult version of the K-SWLS. Second, there is much interest in cross-cultural differences in life satisfaction between Western and Korean children. Accordingly, in the absence of a validated scale for measuring the global life satisfaction of Korean children, a validated Korean version of the SWLS-C would allow many cross-cultural topics about the life satisfaction of Korean children to be properly examined. As well, Korean families are immigrating to Canada in increasing numbers, and having such scales would be most useful to assess self-reported well-being as children transition to Canada.
The present study was undertaken to evaluate the factorial and convergent validities, the internal consistency, and the test–retest reliability of the Korean version of the Satisfaction With Life Scale adapted for children (K-SWLS-C). It was expected that the one-factor structure of K-SWLS-C, found in previous studies (Gadermann et al., 2010), would be confirmed in Korean children, and that the K-SWLS-C would be moderately and positively correlated with satisfaction with important life domains, as has been previously reported (Huebner, 1991; Huebner, Funk, & Gilman, 2000).
Method
Participants and Procedure
Six hundred fifty-three children in fifth or sixth grade (66.2% Grade 6) were surveyed in nine elementary schools in South Korea. Of the 653 participants, 48.0% were male. All 653 students were included in the analyses undertaken to examine factor structure, intercorrelations, and internal consistency of the K-SWLS-C. Of the 653 participants, 289 who completed the K-SWLS-C and the Korean version of the Multidimensional Students’ Life Satisfaction Scale (K-MSLSS; Lee & Lee, 2005) were included in the convergent validity analysis. Students completed the scales in a classroom during class time.
Measures
The SWLS-C is a 5-item self-report questionnaire designed to assess and evaluate life satisfaction of children. The translation process was conducted in the generally accepted manner. Initially, the original SWLS-C was translated by the author, and then, this translated version was back-translated into English by a bilingual translator. This process was then repeated until translational discrepancies were modest. The Multidimensional Students’ Life Satisfaction Scale (MSLSS; Huebner, 1994; Huebner, Laughlin, Ash, & Gilman, 1998) is a 40-item self-report questionnaire designed to evaluate satisfaction with five life domains, that is, family, friends, school, living environment, and self. In this study, the Korean version of the MSLSS was used (Lee & Lee, 2005).
Assessment of Model Fit
Internal consistency reliability was examined using Cronbach’s alpha coefficients with thresholds above .70 and item-total correlation coefficients with thresholds above .30 (Nunnally & Bernstein, 1994). Confirmatory factor analysis was conducted using several indices, that is, the Tucker–Lewis index (TLI), the comparative fit index (CFI), and root mean square error of approximation (RMSEA). Finally, convergent validity between the K-SWLS-C and K-MSLSS was examined using Spearman’s correlation coefficients. The Bonferroni correction procedure was used to address the problem of multiple comparisons (adjusted p value = .003).
Results
Internal Consistency Reliability and Test–Retest Reliability
Cronbach’s alpha coefficient of the K-SWLS-C was acceptable at .91 (threshold of acceptability .70). Using the criterion of .30, item-total correlation coefficients were in an adequate range (.73-.85; see Table 1). These two indices showed that the K-SWLS-C has sound internal consistency. The test–retest reliability of the K-SWLS-C was .62 for a 4-week inter-test period.
Factor Loadings and Item-Total Correlations for Each Item of the K-SWLS-C.
Note. K-SWLS-C = The Korean version of the Satisfaction With Life Scale adapted for children.
Factorial Structure Validity
Based on previous theoretical and empirical research studies, a single factor model was used with confirmatory factor analysis. All factor loadings were significant in the expected directions and exceeded .77 (Table 1). Fit indices for this one-factor model were good (TLI = .998, CFI = .996, RMSEA = .036; Hu & Bentler, 1999). Thus, this model appeared to have good factorial validity.
Convergent Validity
According to Spearman’s correlation analyses, K-SWLS-C was significantly correlated with the friend satisfaction (ρ = .489, p < .001), school satisfaction (ρ = .515, p < .001), family satisfaction (ρ = .583, p < .001), environment satisfaction (ρ = .480, p < .001), and self-satisfaction (ρ = .575, p < .001) of the K-MSLSS with medium and large effect sizes (Cohen, 1988; see Table 2).
Zero-Correlations Between the Factors of K-SWLS-C and the K-MSLSS (N = 289).
Note. All correlations are significant at the .003 level (two-tailed). K-SWLS-C = The Korean version of the Satisfaction With Life Scale adapted for children; K-MSLSS = The Korean version of the Multidimensional Students’ Life Satisfaction Scale.
Discussion
The results of the present study show that the K-SWLS-C has sound internal consistency and test–retest reliability. The K-SWLS-C was found to assess a unitary construct, which is similar to the findings of an earlier study conducted on North American children (Gadermann et al., 2010). In addition, moderate associations were found between the K-SWLS-C and K-MSLSS, which showed adequate convergent validity.
In agreement with earlier studies (Pavot & Diener, 1993), Item 4 of the K-SWLS-C (“So far I have obtained the important things I want in life”) and Item 5 (“If I could live my life over, I would have it the same way”) showed lower item-total correlations and factor loadings than the other items of K-SWLS-C. According to Pavot and Diener (1993), this could have been due to the past orientation of these two sentences, whereas the other three have a present orientation. This speculation should be confirmed by future studies using more diverse measures, which include present and past orientation (Bhullar, Surman, & Schutte, 2015).
The convergent validity of the K-SWLS-C was found to be adequate in the present study, and it was found that the K-SWLS-C was moderately correlated with each of the five domains of the K-MSLSS. These results imply that Korean children report their life satisfaction on the basis of their evaluation of the five domains of the K-MSLSS, and the domains of the K-MSLSS are important for the Korean children.
Several limitations of the present study are worthy of consideration. First, the author enrolled only fifth- and sixth-grade students, whereas the SWLS-C was originally developed for fourth- and eighth-grade students. Thus, there is a need to examine psychometric properties for children across a wide range of ages. Second, measures for evaluating discriminant validity were not included in the present study, and thus, the author suggests a study be conducted that uses scales representing other than well-being (e.g., depressive symptoms).
In conclusion, this study suggests the K-SWLS-C is a well-established instrument for assessing life satisfaction in Korean children, and that the K-SWLS-C includes psychometrically sound items and has unifactor structure. Although the K-SWLS-C would benefit from future studies on children across the age range, the author recommends that the K-SWLS-C be used in epidemiological studies, clinical outcome research, and youth developmental studies.
Footnotes
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.